diff --git a/arch/arm/plat-sunxi/include/plat/i2c.h b/arch/arm/plat-sunxi/include/plat/i2c.h
index d75347b..d57a2c7 100644
--- a/arch/arm/plat-sunxi/include/plat/i2c.h
+++ b/arch/arm/plat-sunxi/include/plat/i2c.h
@@ -193,7 +193,7 @@ Foscl is clock SCL;standard mode:100KHz or fast mode:400KHz
 #define TWI4_BASE_ADDR_START  (SW_PA_TWI4_IO_BASE )
 #define TWI4_BASE_ADDR_END    (TWI4_BASE_ADDR_START + AW_TWI_ADDR_SIZE)
 
-#define I2C0_TRANSFER_SPEED     (400000)
+#define I2C0_TRANSFER_SPEED     (100000)
 #define I2C1_TRANSFER_SPEED     (100000)
 #define I2C2_TRANSFER_SPEED     (100000)
 #define I2C3_TRANSFER_SPEED     (100000)
diff --git a/drivers/i2c/busses/i2c-sunxi.c b/drivers/i2c/busses/i2c-sunxi.c
index 85345e0..05281ca 100644
--- a/drivers/i2c/busses/i2c-sunxi.c
+++ b/drivers/i2c/busses/i2c-sunxi.c
@@ -40,7 +40,7 @@
 #include <plat/system.h>
 
 
-#define SUNXI_I2C_DEBUG
+// #define SUNXI_I2C_DEBUG
 
 #ifdef SUNXI_I2C_DEBUG
 #define i2c_dbg(x...)   printk(x)
@@ -614,7 +614,7 @@ static int i2c_sunxi_core_process(struct sunxi_i2c *i2c)
 #endif
 
     if(i2c->msg == NULL) {
-        printk("i2c->msg is NULL, err_code = 0xfe\n");
+        i2c_dbg("i2c->msg is NULL, err_code = 0xfe\n");
         err_code = 0xfe;
         goto msg_null;
     }
@@ -892,7 +892,7 @@ static int i2c_sunxi_do_xfer(struct sunxi_i2c *i2c, struct i2c_msg *msgs, int nu
 		ret = -ETIME;
 	}
 	else if (ret != num){
-		printk("incomplete xfer (0x%x)\n", ret);
+		i2c_dbg("incomplete xfer (0x%x)\n", ret);
 		ret = -ECOMM;
 		//dev_dbg(i2c->adap.dev, "incomplete xfer (%d)\n", ret);
 	}
